Carburetor



Oct. 31, 1933. F, 5 ASELTlNE 1,933,134

CARBURETOR Filed May 31, 193 0 2 Sheets-Sheet 1 gmwvtoo FkED E ASELT/NE.

al ke own,

Oct. 31, 1933. F. E. ASELTINE CARBURETOR Filed May 51, 1930 2 Sheets-Sheet 2 Patented Oct. 31, 1933 UNITED STA 1,933,134 CARBURETOR Fred E. Aseltine, Dayton, Ohio, assignorto Delco Products Corporation, Dayton, Ohio, a corporation of Delaware Application lliay 31, 1930. Serial No. 457,695

13' Claims.

This invention relates to carburetors for internal combustion engines, and while a. preferred form of the invention is shown herein as embodied in that type of carburetor which comprises a plurality of primary mixing chambers, each of which delivers a primary mixture of fuel and air to one of a plurality of secondary mixing chambers in which the primary mixture is mixed with additional air under certain operating conditions, it will be understood that the invention is not limited to that type of carburetor and is of enapplication to any form of carv vide means for preventing enrichment of the mixture on deceleration occasioned by a rise .in the level of fuel in the float chamber.

In carburetors in which the'fioat is not concentrically arranged with respect to the float chamber and which are so mounted on the engine that the float lies to the rear of the axis of the float chamber, the float will drop, on deceleration to a position below that it should assume, admitting fuel to the float chamber until the level is higher therein than it should be, which results in too great a head on the fuel" at the nozzles and too great a flow of fuel therefrom to form a mixture of proper proportions. The reason for this is seen in the surge of fuel toward the forward side of the fuel bowlwith respect to the vehicle. When the operator takes his foot from the accelerator on deceleration, the throttle is automatically closed and the slowing down of the vehicle causes thefuelto surge toward the front side of'the fuel bowl, lowering the level of the fuel on the rear side where the float is positioned. This action permits the -float;to drop, opening the fuel inlet to the fuel bowl wide and permitting fuel to flow rapidly into the float chamber until the fuel level rises sufficiently to close the float valve. This action raises the level off-he fuel in the float chamber above the normal, resulting in the enrichment of the mixture above referred to. v

' According to the present invention, this objectionable action is overcome by providing means operated by the throttle as it is closed, which holds the float up, preventing the admission of fuel as described.

Further objects and advantages of the present invention will be apparent from the following description, reference being had to the accompanying drawings wherein a preferred embodiment of one form of the present invention is clearly shown. f

In the drawings:

Fig. 1 is a side elevation of a carburetor, part1 in section, constructed inacco-rdance with this invention.

Fig. 2 is a section on the line 2-2 of Fig. 1,

Es PATENT OFFICE partly. broken away to show certain parts in elevation and omitting certain parts.v

Fig. 3 is a side elevationshowing certain parts in section.

The drawings illustrate a carburetor unit ed to admit air thereto and a casting 14 secured r to the bottom of the main. housing in any desirable way. The latter having various fuel pas.- .sages and dashpot chambers formed therein as in the above application. The main housing is provided with an annular shoulder 16 against which a sheet metal float chamber 18 is held tight by a screw 20 screwed into the casting 14. Fuel is admitted through a pasage controlled by a valve, as shown in Fig. 3. The fuel valve is cons trolled by a. float 22, which, asclearly shown in Fig.12, lies to the right of the axis of the float chamber and toward the'rearf of the vehicle on which the carburetor is used.

horizontal fuel channel 23 formed in the carburetor casting. I This channel connects with averticalfuel channel 25, having an enlarged lower end in which is a nipple 27, provided with a restriction 29, forming av seat for a fuel valve31, resting on an arm 33, projecting from the float Fuel is conducted from the main fuel tank .to

nozzles 24,1ocated in primarymixin'g chambers the valve closed to facilitate starting, all of which is fully shown and described in the above application.

The air valve 27 admits air to a main air chamber 36 from which it flows to the primary mixing chambers and to thesecondary mixing chambers, the flow of air to the secondary mixing chambers being controlled by a secondary throttle secured to a shaft 40 journalled in the main housing, which is operated by a primary throttle .41 through the medium of an operating link 42 connected to an arm 44, secured to the shaft flipand to an operating plate 46 secured to one .endof .said primary throttle as fully described .insaid earlier application. The operating plate 46 is rotated in a clockwise direction, as.viewed in Fig. 1, on opening of the primary throttleand inthe' reverse, or counter-clockwise direction on closing of :said throttle.

Piyotally connected .to an ear 18 projecting from the operating plate 46,?is arrodfimwhich at its lower'end extends into a tube :52 :closedzat bottom :and projecting 'upmdl-y strum piston 54 of a fuel pump which slirlable :in 1a pump cylinder 56, this pump being operated -:on :every opening movement of the prirnaa'y'throitle to supply additional fuel :to :the summary mixing chambers during the acceleration :period as set forth in the earlier application.

Secured to the :piston rodzby brazing or otherwise, and extending lateraillytherefimmris an ear 58 to which is secured by theme-W60, an angular fiat bar 62 formed of sheetsmetal. This 'barcornprises a portion 64 extending from its :point of attaclmient :to the car 58 toward the :rear of the carburetona lateral portion 66 extending transversely 0f thekcarbm'etor :as shown in Fig. 2, .a portion 68 which projects downwardly :from the ia'teral part 66 and connects with :a forwardly extending portion 70, which lies immsdiatelybeheath the float 22.

when the parts .are the position :shown in the drawings with the throttle closed, the part 70 of the bar 62 occupies .apos'itionsuch that the float 'will not be allowed to drop 'more than enough to permit the fuel valve operated thereby to open more than enough to pennit just :enough to flow into the float chamber totsatisfy the demands of the engine when'running very slowly under load, -or idling. As the throttle :is opened, the bar is lowered away from the float so that opening of the float is controlled entirely by the level of liquid within the fined; chamber. when the throttle is closed, however, the ibll lifts :np the float so that it is almost closed for the purpose previously described. is particularly useful to prevent enriching of the mixture when the vehicle is stopped suddenly by use :of the brake. When the operators foot :is removed from the foot accelerator -pedal and the brake-applied, the spring w'hich:is ordinarily em- :ployedto closethe throttle pulls it rapidly closed and at same time the bar-62 isefiective to lift the finat'so that it isnot' permitted to :move to a relatively wide open position on the sudden surgin: forward of the fuel within the float chamber, which occurs'when the vehicle .is .stopped sudde ly- While the form of embodiment of the present invention as hereindisclosed, constitutes a predenied .form, it :is to :be understood that other forms might be adopted, all coming within the scope-of the which follow. as follows:;

1. A carburetor for internal combustion engines comprising a mixture passage, means for supplying fuel and air thereto, a throttle for regulating the flow through said mixture passage, and means operated by the throttle as said throttle is moved toward closed position and before the throttle reaches fully closed position to prevent enriching of the mixture during deceleration.

2. A carburetor for internal combustion enigines comprising a mixture passage, means for supplying fuel and air thereto, a throttle for regula'ting the flow through said mixture passage, .9. .fuel reservoir, and means operated by the throttle to restrict the flow of fuel to the fuel reservoir assaid throttle is moved toward closed position ,but before it reaches fully closed position, whereby the flow of fuel to the reservoir is restricted but not entirely prevented so that the engine can continue to operate.

-3.A carburetor for internal combustion engines comprising amixture passage, means for supplying :fuel and air thereto, a throttle .for regulating the flow through said mixture passage, :a fuel .reservoir, 1a float therein adapted to control the admission of fuel to said fuel reservoir, and .means for moving said float to a position to restrict the admission of fuel to said reservoir .as said throttle is "moved toward closed position and before the throttle reaches fully closed position .to prevent enriching of the mixture during deceleration.

4. A carburetor for internal combustion engines comprising a mixture ,passage, means for supplying .fuel and air thereto, athrottlefor regulating the .flow through said mixture passage, a ."fuel reservoir, :a .floa't therein adapted to 5.0011- trol the admission of fuel to said reservoir :and positioned to one side of the axis of said reservoir, whereby 'on deceleration :the level of fuel :beneath the float tends to fall, and means -en- :gaging the Qfloat to :hold it in position to restrict the admission of fuel to the fuel reservoir, on

lowering of the :fuel level beneath the :float .dur-

:sage, a fuel reservoir, :a float therein adapted to control the admission of .fuel to said reservoir and positioned to one side of the axis of said reservoir, whereby the fuel level :beneath the zfloat tends to fall on deceleration and means operated by the throttle on movements thereof toward closed position towengage .the float so .asitoholdrit in position to restrict :the admission nfiuelto the fuel reservoir, on lowering of :the ."fuel =leveltheneath the float :during deceleration.

6. A carburetor for internal combustion en- 'gines comprising a :primary carbureting device -for supplying-Ia primary "mixture of fuel and air :to a secondary mixing ,:chamber in which said primary mixture may fbe'mixed withaddiitional air, means for supplying-fuel and air to :said primary mixturepassage, a primary throttle regulating the tflow therethrough and means operated by the primary throttle as :said throttle is moved toward closed position and .beforeit reaches fully closed position in order to prevent enriching of the primary mixture duringthe period of deceleration. 7 l. Afcarburetor .-for internal combustion engines comprising a primary carbureting device for supplying a primary mixture of Iceland .air to a secondary mixing chamber, in which said ulating the flow therethrough, a fuel reservoir and means operated by the primary throttle as said throttle is moved toward closedposition and before it reaches fully closed pasition in order to restrict the flow of fuel to said reservoir during periods of deceleration accompanying closing movements of the throttle.

8. A carburetor for internal combustion engines comprising a primary carbureting. device for supplying a primary mixture of fuel and air to a secondary mixing chamber, in which said primary mixture may be mixed with additional air, means for supplying fuel and air to said primary mixture passage, a primary throttle regulating the flow therethrough, a fuel reservoir, 9. float therein adapted to control the admission of fuel to said reservoir and means engaging'the float and operated by the primary throttle tomove said float to a position to restrict the admission of fuel to said reservoir on movements of saidtle toward closed position, said means comprising a member movable with the throttlein a generally vertical direction and a bar extending from said member to a position beneath the float.

10. A carburetor for internal combustion engines comprising a mixture passage, means for supplying fuel and air thereto, a throttle for regulating the flow through said mixture passage, a fuel reservoir, a float therein adapted to control the admission of fuel to said reservoir, a fuel pump operable bythe throttle on opening movements thereof to supply additional fuel to the mixture passage during the acceleration period and means operated by said pump to restrict the admission of fuel to the reservoir, during the movement of the throttle toward closed position, to prevent enrichment'of the mixture during deceleration.

11. A carburetor for internal combustion engines comprising a mixture passage, means for supplying fuel and air thereto, a throttle for regulating the flow through said mixture passage, a fuel reservoir, a float therein adapted to control the admission of fuel to said reservoir, a fuel pump operable by the throttle on opening move-- tle toward closed position to prevent enrichment of the mixture'during deceleration.

12. A carburetor for internal combustion en gines comprising a mixture passage, means forsupplying fuel and air thereto, a throttle for regulating the flow through said mixture passage, a fuel reservoir, a float therein adapted to control the admission of fuel to said reservoir, a fuel pump operable by the throttle on opening movements thereof to' supply additional fuel to the mixture passage during the acceleration period, a pump operating member extending from the pump to the throttle and adapted to be reciprocated in a substantially;vertical plane as the throttle is opened and closed, and a bar extending from said member to" a point beneath the float, whereby said bar is adapted to move the float .toward closed position asthe throttle is moved toward closed position.

13. A carburetor for internal combustion engines comprising a mixture passage, means for supplying fuel and air thereto, athrottle for regulating the flow through said mixture passage,

afuel reservoir, a float therein adapted to control the admission of fuel to said reservoir, a fuel pump adapted to supply additional fuel to the mixture passage, to enrich the mixture during the acceleration period, and a single means effective to operate said pump as the throttle isopened, and to operate the float to restrict the admission of fuel to the reservoir as the throttle is moved toward closed position.

- FRED E. ASELTINE. 

